A photovoltaic cell is a generator, also called photocell, that uses the photovoltaic effect. The photovoltaic effect can be defined as the appearance of a potential difference between two layers of a semiconductor slice which have opposite conductivities, or between a semiconductor and a metal, under the effect of a light flow. A photovoltaic cell generates a direct current.
A semiconductor is generally a solid material of which the resistivity, intermediate between that of metals and that of insulating materials, differs under the influence of factors such as temperature, illumination, electric field, etc.
The main known semiconductor materials are germanium, silicon and selenium.
A portable solar charger is known and described in WO 2004/077577. This charger comprises a flexible photovoltaic panel permanently fixed on a flexible textile. Said solar or photovoltaic panel can be sewed according to its inactive edges to the flexible textile sheet, or glued, or even welded by heat or ultrasonic input.
The manufacture of this type of solar charger is still traditional nowadays. Techniques that allow manufacturing these assemblies, resulting from assembling a textile sheet and one or more photovoltaic flexible panels, having great dimensions, do not exist industrially.
These small dimensioned chargers have a small surface for collecting incident rays. Furthermore, when they are arranged to form solar protective panels, for instance so as to constitute a blind, the storage housings must be dimensioned at least for receiving the textile sheet in a winded way, having a thickness that has substantially increased, even doubled, once assembled with one or more photovoltaic panels.